A Comparison Of The Traditional Method And The PCR Method In The Identification Of M. Tuberculosis Complex

Objective： to compare and analyze the traditional method of identifyingMycobacterium tuberculosis complex with PCR method, and provide a scientific basis forclinical application.Methods：Strain identification was conducted on the isolates of313sputum samples from patients diagnosed with pulmonary tuberculosis in KashgarThoracic Hospital from April2010to May2011using traditional method (p-nitrobenzoicacid and thiophene-2-carboxylic acid hydrazide) of identifying mycobacteriumtuberculosis and PCR method, respectively.100samples (from the313) of mycobacteriumtuberculosis, Mycobacterium bovis and type I mycobacterium africanum were chosenpurposely to examine the reliability of the above two methods using the SpoligotypingTest （the preferred method of identification of mycobacterium tuberculosiscomplex,especially mycobacterium bovis and BCG can be described ad the goldstandard）.Results：253mycobacteria tuberculosis,60mycobacteria bovis,o type Imycobacterium africanum were detected through the traditional method;however, whenadopting the PCR method,306mycobacteria tuberculosis,1mycobacterium bovis and6Type I mycobacteria africanum were detected. The difference between the two methodswas not statistically significant (χ~2=5.05,P=0.08).(the frequency was examined), theaccordance rate being79.87%(250/313).Although there was no statistical significance inthe results by the two methods, when looking at Mycobacterium bovis alone, thedifference was statistically significant (χ~2=4.16,P=0.04). Therefore,when we adopted theSpoligotying test to examined the100purposively chosen samples(40mycobacteriatuberculosis,60mycobacteria bovis,0type I mycobacterium africanum were detectedthrough the traditional method;however,PCR method,93mycobacteria tuberculosis,1mycobacterium bovis and6Type I mycobacteria africanum were detected.)2mycobacteria bovis、92mycobacteria tuberculosis、6type I mycobacteria africanumwere identified by the Spoligotyping,however2connot be identified. According to the result of the Spoligotyping Test, the accordance rates by the traditional method and PCRwere38.78%（2+36/98） and98.98%(1+90+6/98), respectively.Conclusion：AfterSpoligotyping method detection shows that traditional methods of strain identification ofMycobacterium tuberculosis complex compared with the PCR method is moretime-consuming, tedious, and can not be accurately identified strains, the PCR method canaccurately and quickly identified to sub-species.